The steering and handling of a snowmobile is highly dependent on the proper alignment of the front skis (hereinafter simply the skis). If the skis are misaligned, i.e. not parallel, the snowmobile will handle poorly and tend to veer off course. Extreme misalignment can make the vehicle almost impossible to drive. The “toe” of the front skis is a term of art referring to the misalignment of the skis. “Toe-in” means that the skis converge, i.e. point inwardly with respect to each other in the forward, travel direction of the vehicle whereas “toe-out” means that the skis diverge, i.e. point outwardly with respect to each other in the forward, travel direction.
As is known by those of ordinary skill in the art, a very small degree of toe-out is sometimes desired since this creates a force which forces the skis to the toed-out position and thus takes up any slack that might arise due to wear and tear or due to manufacturing tolerances. Although it is desired to make the skis perfectly parallel, they are, in practice, often assembled either slightly toed-in or toed-out, and therefore it is sometimes (but certainly not always) preferable to err on the side of toe-out during initial alignment of the skis.
Misalignment of the skis can arise because of human error in the initial installation of the skis and also because of collision with foreign objects, which can knock the skis out of alignment, as is the case with most other land vehicles.
Referring to FIG. 1, the initial alignment of a pair of skis 26 of a conventional snowmobile 10 is conventionally performed by eye, via iterative readjustments of left and right steering rods 29 connected respectively to the skis. When initially connected to the snowmobile 10, the steering rods 29 are normally not equal in length on both sides of the snowmobile. In order to initially align the skis 26 to ensure that both are pointing straight ahead, the handlebars 36 are first positioned in the straight-ahead direction. Then, by measuring the distance between the two skis 26, once at the front end of each of the skis and once at the rear end of the skis, one can determine if the skis are misaligned. In other words, a distance D1 is measured between corresponding points 25 on the front of the skis and a distance D2 is measured between corresponding points 27 on the rear of the skis. If D1<D2, then the skis are toe-in. If D1>D2, then the skis are toe-out. Ideally, the D1=D2 so that the skis are aligned, i.e. parallel to each other.
If the skis are misaligned, the lengths of the steering rods are altered to realign the skis. Each time the steering rods are altered, the distances D1 and D2 are re-measured to see if they are now in alignment with each other. Each subsequent iteration (measurement and adjustment) brings the skis closer and closer into parallel alignment with each other.
In the prior art, the traditional methods of determining if the skis are indeed pointing straight ahead, i.e. that they are sufficiently parallel to each other, is by measuring the distances D1 and D2 between the skis at front and rear locations. However, measuring front and rear distances is fraught with error as the exact distance between the skis is quite difficult to repeatedly measure since there are no easy reference points on the skis.
The skis typically have “skags” (i.e. a generally straight steel runner on the underside of each ski) that are designed to be parallel to each other but, since these are on the underside, these are not easily accessible.
Furthermore, the skis themselves are not straight-edged along their length, i.e. they generally are shaped with curved side edges. Thus, it is not a simple task to simply measure the distance from one ski edge to another in a consistent and repeatable manner since the inner and outer edges do not define a clearly identifiable reference point. To arbitrarily select forward and rearward reference points on curved-edge skis generally results in poor measurements and continued misalignment of the skis.
Yet another prior-art approach to aligning skis (which is illustrated in FIG. 2) has been to use the studs that attach the skag 31 to the ski 26 as reference points. The studs 33 are normally aligned with the centre of the skag 31, traversing the bottom surface of each ski 26. A user can then align a tape measure 35 above the tops of corresponding studs 33 on each ski 26 to measure the distance D between the skags 31. When the skags 31 are aligned with each other, so are the skis 26 since the skags are affixed to the skis in a parallel relationship. However, this latter technique requires two people since the tape measure must be held inline with the studs while being above each stud since the stud is below the plastic side wall 37 of the ski, thus preventing the measuring tape 35 from being hooked directly onto the stud 33. Moreover, since the tape measure 35 must be held exactly above the stud 33 to get an accurate measurement, this technique naturally introduces a substantial measuring error.
Therefore, it would be highly desirable to provide a snowmobile ski that overcomes at least one of the deficiencies of the prior art as described above.